initial commit

ptycho/utils_electron/crop_pad.m

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+% CROP_PAD adjusts the size by zero padding or cropping
+% Inputs: 
+%   **img                input image
+%   **outsize            size of final image
+% *optional:*
+%   **fill               value to fill padded regions 
+% returns: 
+%   ++imout              cropped image 
+
+
+function [ imout ] = crop_pad( img, outsize, fill)
+
+if nargin < 1
+    fprintf('CROP_PAD: adjusts the size by zero padding or cropping\n');
+    fprintf('crop_pad(img, outsize)\n');
+    return
+end
+
+Nin = size(img);
+
+if isempty(outsize) || all(outsize(1:2) == Nin(1:2))
+    imout = img;   % if outsize == [], return the same image without changes 
+    return
+end
+
+Nout = outsize(1:2);
+
+if nargin < 3
+    fill = 0;
+end
+
+
+
+center = floor(Nin(1:2)/2)+1;
+
+imout = zeros([Nout,Nin(3:end)],'like',img);
+
+if fill ~= 0 
+    imout = imout + fill; 
+end
+
+centerout = floor(Nout/2)+1;
+
+cenout_cen = centerout - center;
+imout(max(cenout_cen(1)+1,1):min(cenout_cen(1)+Nin(1),Nout(1)),max(cenout_cen(2)+1,1):min(cenout_cen(2)+Nin(2),Nout(2)),:,:) ...
+    = img(max(-cenout_cen(1)+1,1):min(-cenout_cen(1)+Nout(1),Nin(1)),max(-cenout_cen(2)+1,1):min(-cenout_cen(2)+Nout(2),Nin(2)),:,:);
+
+if ~isreal(img)
+    imout = complex(imout);
+end
+
+end
+